Within the realm of violence, work-related violence has recently been recognized as a major problem. While there is an emerging literature pertinent to work-related homicides, there is a serious deficiency in the knowledge of non-fatal work-related violence and the associated risk factors. This proposed study is designed to identify the magnitude of the problem within a major occupational population and to identify specific risk factors, using a case-control design. The primary aims are to determine the relation between work-related violence in a cohort of registered and licensed practical nurses and: (1) personal exposures, including patient contact hours, workload, shifts worked, illness/injury history including prior work and non-work-related assault injuries, use of alcohol, tobacco, and other drugs, and demographics; (2) environmental situations/exposures in the workplace such as types of hospitals/department/speciality wards, staffing patterns, management protocols, physical environment (lighting, barriers, room configurations); general social environment (support/tolerance for harassment and abuse); (3) characteristics of others in the environment (other workers, patients, visitors), numbers and types of patients/relevant diagnoses/hospitalization duration, and demographics. Initially, a survey instrument will be sent to a random selection of nurses who worked in the state of Minnesota during a 12 month period to identify persons who did and did not experience work-related events meeting the definition of violence. Subsequently, a nested case-control design will be used to examine the relation between potential risk factors and work-related violence. For each case, three controls will be sampled from the population at risk during the study period. A questionnaire will then be sent to the cases and selected controls to obtain data on workplace exposures including the characteristics of nurses and significant others in the workplace and surrounding environmental factors. Cases will be questioned about their exposures prior to and during the incident. Controls will be questioned about their exposures on a randomly selected time from the study period to provide the person-time exposure information. Validity relevant to selection bias and information bias will be evaluated through substudies. This study design will enable us to calculate rate ratios for the effect of exposures of interest on the rate of injury. From this effort, specific prevention and control strategies can be developed more realistically.